Agreed with FBKSan, day 6 isn't particularly feasible. Valdez is a good 5 hour drive from Anchorage, and 2.5 hours from Glennallen. So you'd be looking at 10 hours in the RV, at least, bearing in mind that RV's don't travel fast, and doing a lot of backtracking.

When driving in Alaska, you have to keep in mind that there are no freeways outside of the Anchorage/Mat-Su area. The Glenn "Highway" is actually a two-lane road that is very narrow and slow in spots. I have an Acura that allows me to zip through there pretty easily, but an RV is going to have to take it slow (and piss off Alaskans who get stuck behind you and believe it's our God-given right to drive 110 mph )

If it fits into your schedule, I'd recommend taking the ferry from Valdez to Whittier. You'd save yourself a lot of miles and stress that way.

Otherwise, it sounds like you have an outstanding, if full, trip planned.